Lumbricillus pagenstecheri (Ratzel, 1869) Cryptic species A

Klinth, Marten J., Rota, Emilia & Erseus, Christer, 2017, Taxonomy of North European Lumbricillus (Clitellata, Enchytraeidae), ZooKeys 703, pp. 15-96 : 35-37

Lumbricillus pagenstecheri (Ratzel, 1869) Cryptic species A Fig. 14, Table 2

Material examined.

SMNH 152766 (CE1896), SMNH 152767 (CE1897), SMNH 152768 (CE1899), SMNH 152769 (CE2497), SMNH 152770 (CE2498) & SMNH 152771 (CE2500), six mature specimens from Sweden. For information on specimen collection localities and GenBank accession numbers see Appendix 1.

Description.

White to yellow worms. Length (fixed worms) more than 2.8-9.3 mm (amputated specimens), first 15 segments 2.4-4.2 mm long, width at clitellum 0.59-0.75 mm. More than 17-40 segments. Chaetae sigmoid (Fig. 14A). Dorsal bundles with 2-5 chaetae anterior to clitellum, 2-5(6) chaetae in postclitellar segments. Ventral bundles with (2)4-7 chaetae anterior to clitellum, (2)3-6(8) chaetae posteriorly. Each worm’s longest measured chaetae 70-95 µm long, about 5-8 µm wide. Clitellum extending over XII–XIII. Head pore at 0/1. Epidermis with transverse rows of gland cells.

Coelomocytes numerous, 15-25 µm long, spindle-shaped, oval, round, granulated with distinct nucleus. Paired pharyngeal glands present in IV, V and VI; two first pairs connected dorsally, third pair with uncertain connection (Fig. 14B). Dorsal vessel originating in XIII. Nephridia observed in VII–X and XII–XXI, 120-130 µm long, anteseptale funnel only, postseptale oval, tapering into posterior efferent duct. Brain with shallow posterior incision.

Male genitalia paired (Fig. 14D). Testes originating in XI, extending forwards into X, sometimes IX, with testis sacs forming regular club-shaped lobes. Sperm funnels in XI, 210-300 µm long, 145-225 µm wide, making them about as long as wide or twice as long as wide, funnels gradually tapering towards vasa deferentia. Most of vasa irregularly coiled in XII, 10-15 µm wide. Penial bulbs round, 135-185 µm in diameter. Ovaries in XII. About two to eight mature eggs present at a time.

Spermathecae (Fig. 14C) in V, club-shaped, with distinct ampulla. Ectal duct narrow, about as long as ampulla, abruptly widening into ampulla. Ampulla round, entally connecting with oesophagus. Sperm arranged in circular masses in ampulla. Spermathecae 140-215 µm long, 75-110 µm wide at widest part of ampulla. Two groups of gland cells, one covering ectal duct, the other surrounding ectal pore. Gland cells surrounding ectal pore forming compact mass, slightly lobed, whole glandular body 80-195 µm in diameter at its widest part. Two midventral subneural glands in XIII–XIV, 130 µm and 95 µm long, respectively.

Geographical distribution including BOLD data.

Genetically identified from Sweden; also recognized from Canada and Denmark (BIN-number: BOLD:AAF9627).